Over time, energy density in batteries has increased, while packaging size for the batteries has decreased. Lithium ion batteries are an example of high energy density batteries and have become the preferred battery technology for items such as, consumer electronics, electric vehicles, battery backup systems, and other energetic systems requiring a mobile and rechargeable power source. A byproduct of high energy density is that lithium ion batteries pose a greater safety risk than lower energy density technologies, due to the amount of chemical energy stored in a small package. A mechanism by which high energy density batteries fail energetically is called thermal runaway, a condition where the chemical reaction inside a single cell becomes unstable due to excessive heat which may be generated by an internal defect or by other means. Thermal runaway causes the single cell to continue to heat up at an ever-accelerating rate until the structural integrity of the single cell is compromised or the single cell combusts.